Documentation/devicetree/bindings/misc/cs40l20.txt

CS40L20/CS40L25/CS40L25A/CS40L25B Boosted Haptics Driver

Required properties:

  - compatible : One of "cirrus,cs40l20", "cirrus,cs40l25", "cirrus,cs40l25a"
    or "cirrus,cs40l25b".

  - reg : The I2C slave address of the device.

  - VA-supply, VP-supply : Regulators for the device's VA and VP supplies,
    respectively. See the following:
    Documentation/devicetree/bindings/regulator/regulator.txt

  - cirrus,boost-ind-nanohenry : Boost inductor value, expressed in nH. Valid
    values include 1000, 1200, 1500 and 2200.

  - cirrus,boost-cap-microfarad : Total equivalent boost capacitance on the VBST
    and VAMP pins, derated at 11 volts DC. The value must be rounded to the
    nearest integer and expressed in uF.

  - cirrus,boost-ipk-milliamp : Boost inductor peak current, expressed in mA.
    Valid values range from 1600 to 4500 (inclusive) in steps of 50.

Optional properties:

  - reset-gpios : GPIO used for resetting the device.

  - interrupt-parent : Single phandle representing the interrupt controller to
    which the /ALERT pin is connected (silicon revision B1 only).

  - interrupts : interrupt specifiers for the device (silicon revision B1 only).
    See the following:
    Documentation/devicetree/bindings/interrupt-controller/interrupts.txt

  - cirrus,refclk-gpio2 : Boolean for configuring the device to expect its
    32.768-kHz reference clock on the REFCLK/GPIO2 pin. If this property is
    omitted, the device expects its 32.768-kHz reference clock on the
    ASP_BCLK/REFCLK pin. This property is ignored for silicon revision B1 as
    reference clock selection is configured automatically in that case.

  - cirrus,f0-default : Default LRA resonant frequency (f0), expressed as
    follows: cirrus,f0-default = f0 (Hz) * 2^14. This value represents the
    frequency used during playback of PWLE segments specified with frequency
    equal to f0; it also serves as the unit-specific f0 input to the click
    compensation algorithm. It can be overwritten at a later time by writing
    to the f0_stored sysfs control.

    If this value is omitted or specified as zero, the measurement recorded in
    the f0_measured sysfs control is used. If LRA diagnostics has not been
    administered and f0_measured is uninitialized, 2621440 (160 Hz) is used.

  - cirrus,f0-min : Minimum LRA resonant frequency (f0) that may be written to
    the f0_stored sysfs control, expressed using the same numerical format as
    cirrus,f0-default. If this value is omitted or specified as zero, no lower-
    bound validation is performed.

  - cirrus,f0-max : Maximum LRA resonant frequency (f0) that may be written to
    the f0_stored sysfs control, expressed using the same numerical format as
    cirrus,f0-default. If this value is omitted or specified as zero, no upper-
    bound validation is performed.

  - cirrus,redc-default : Default LRA series resistance (ReDC), expressed as
    follows: cirrus,redc-default = ReDC (ohms) / 5.857 * 2^17. This value
    represents the unit-specific ReDC input to the click compensation algorithm.
    It can be overwritten at a later time by writing to the redc_stored sysfs
    control.

    If this value is omitted or specified as zero, the measurement recorded in
    the redc_measured sysfs control is used. If LRA diagnostics has not been
    administered and redc_measured is uninitialized, 340787 (15.2 ohms) is used.

  - cirrus,redc-min : Minimum LRA series resistance (ReDC) that may be written
    to the redc_stored sysfs control, expressed using the same numerical format
    as cirrus,redc-default. If this value is omitted or specified as zero, no
    lower-bound validation is performed.

  - cirrus,redc-max : Maximum LRA series resistance (ReDC) that may be written
    to the redc_stored sysfs control, expressed using the same numerical format
    as cirrus,redc-default. If this value is omitted or specified as zero, no
    upper-bound validation is performed.

  - cirrus,gpio1-rise-index : Specifies the wavetable index mapped to GPIO1
    rising edges. If this value is omitted, specified as zero or exceeds the
    maximum available index in the wavetable, GPIO1 rising edges are mapped to
    index 1.

  - cirrus,gpio1-fall-index : Specifies the wavetable index mapped to GPIO1
    falling edges. If this value is omitted, specified as zero or exceeds the
    maximum available index in the wavetable, GPIO1 falling edges are mapped to
    index 2.

  - cirrus,gpio1-fall-timeout : Specifies the number of 48-kHz periods for
    which the device remains in the active state in search of a GPIO1 falling
    edge, following a GPIO1 rising edge (the latter of which renders the device
    active). If a GPIO1 falling edge does not arrive within this timeout, the
    device automatically returns to the standby state and the subsequent GPIO1
    falling edge is ignored. If this value is omitted or exceeds the maximum
    timeout (8388607) then a default of 240000 is assumed (corresponding to
    240000 / 48000 = 5 seconds). If this value is specified as zero, the timeout
    is effectively disabled.

  - cirrus,gpio1-mode : Specifies the operating mode of the GPIO1 pin, equal to
    one of the following.

    0 = enabled by default
    1 = disabled by default
    2 = disabled by default, but automatically enabled and disabled upon suspend
        and resume, respectively

    If this value is omitted or given an invalid value, mode 0 (enabled by
    default) is assumed. Regardless of mode, the GPIO1 pin can be enabled or
    disabled at will from user space using the gpio1_enable sysfs control.

  - cirrus,hiber-enable : Boolean for instructing the device to enter and exit
    hibernation mode upon suspend and resume, respectively. Hibernation mode is
    supported by silicon revision B1 only. If this property is omitted, the
    device remains in standby and automatic entry into hibernation mode is
    effectively disabled.

Examples:

  cs40l20: cs40l20@43 {
    compatible = "cirrus,cs40l20";
    reg = <0x43>;
    reset-gpios = <&gpio0 54 0>;
    VA-supply = <&dummy_vreg>;
    VP-supply = <&dummy_vreg>;
    cirrus,boost-ind-nanohenry = <1000>;
    cirrus,boost-cap-microfarad = <4>;
    cirrus,boost-ipk-milliamp = <4500>;
    cirrus,refclk-gpio2;
  };

  cs40l25a: cs40l25a@43 {
    compatible = "cirrus,cs40l25a";
    reg = <0x43>;
    reset-gpios = <&gpio0 54 0>;
    interrupt-parent = <&gpio0>;
    interrupts = <55 8>;
    VA-supply = <&dummy_vreg>;
    VP-supply = <&dummy_vreg>;
    cirrus,boost-ind-nanohenry = <1000>;
    cirrus,boost-cap-microfarad = <4>;
    cirrus,boost-ipk-milliamp = <4500>;
  };